The power supply and light emission controller of the invention is intended to replace the usual relatively heavy, costly and inefficient transformer power supplies used in the prior art to energize cold cathode luminous tubes; and the power supply and controller of the invention also serves to improve the light emission characteristics of such luminous tubes. For example, a power supply and light emission controller constructed in accordance with the concepts of the present invention may be built with a weight of less than one-third the weight of an equivalent prior art transformer power supply, approximately two-thirds the size of the prior art transformer power supply, and at a lower cost than the prior art transformer power supply.
Specifically, as compared with the prior art transformer power supply, a power saving of the order of 35% may be achieved by the solid state power supply and light emission controller of the present invention, and a weight saving of the order of 85% may be achieved. In addition, and as noted above, a cost saving may be realized and improved reliability may be achieved. The solid state power supply and light emission controller of the invention also exhibits an improved power factor as compared with the prior art transformer power supply, in that the power factor of the present invention is nearly unity or slightly leading, whereas the power factor of the prior art transformer power supply is lagging.
As described briefly above, the solid state power supply and light emission controller of the invention provides a regulated light output in the presence of variations in line voltage and ambient temperature. The power supply of the invention, as mentioned above, may be used with alternating current as well as with direct current voltage sources.
Specifically, the solid state power supply and light emission controller of the present invention has an efficiency factor of the order of 80%, and it can regulate the light emission from a cold cathode luminous tube over a variation in line voltage from 90-150 volts, and through variations in line frequency from 40 Hz-500 Hz.